How to make labels on my dendrogam look more clear and visible

Dear group, 
 I have a matrix with readings for ~180 variables
observed in 240 conditions. 

I am doing a hierarchical clustering method (hclust)
by calculating eucledian distances among them. 

When I plot the dendrogram from hclust, all my
variables at the end of the branches are cluttered. I
cannot read them properly. 

I tried using :

x11(width = 100, height = 70, pointsize = 10)
plot(mydat.hcluster)

and also by

x11(width = 1000, height = 300, pointsize = 10)
plot(mydat.hcluster)

I could not make the dendrogram branches go wide and
make variables at the end of braches more legible. 


Can any one please help me to make a good diagram so
that I can see the lables at the end of branches more
clearly. 

Thank you. 

cheers
Sri

postscript("mydendogram.ps", height=800, width=2000, pointsize=[????])
plot(mydendogram)
dev.off()